Found in a 1947 publication, this circuit uses 4 parallel/push-pull tuber in the output stage. The circuit employs dual power supply with two rectifier tubes.
In the figure we have an interface using an optical coupler and the comparator LM339 or any...
This circuit for cars with mechanical breakers (contact breakers) was found in the April 1969...
This circuit can be used to show the direction of current flow in semiconductors, such as LEDs....